DESCRIPTION: Dr. Wessling-Resnick's overall aim is to understand the mechanism of iron transport across membranes. This is a very important problem both from the clinical and basic biology point of view. She has identified a protein called SFT, which is required for the Transferrin independent transport of Fe in Xenopus oocytes and in a preerythroid cell-line K562. SFT has some similarities with the ABC or ATP-Binding Cassette transporters. The three major aims of this proposal are: (1) to characterize the role of SFT in Fe transport; (2) to understand how SFT is localized to both the plasma membrane and endosomes; and (3) to identify the cis-acting elements that regulate the intracellular levels of SFT.